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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Relationships between water quality, species composition, biodiversity and ecosystem function in lakes and flooded pits exposed to uranium mining activities in Northern Saskatechewan

Helps, Devin Murray 25 May 2009 (has links)
Uranium mining activities have the potential to impact aquatic systems through mine drainage (runoff) and the release of treated effluent into nearby watersheds. Such anthropogenic exposure can lead to elevated concentrations of metals and major ions, which may impact aquatic biota. Previous studies have looked at the effects of water quality on aquatic biota within flooded pit lakes and natural lakes that have been exposed to various mechanisms of mining exposure. However, the literature often only examines the effects of a limited number of contaminants on a limited number of species. Researchers have rarely looked at the effects of multiple contaminants on species composition, biodiversity and ecosystem function in aquatic systems. This study uses a multivariate approach to look for relationships between water quality (24 variables), plankton species composition and abundance, biodiversity (richness and evenness) and ecosystem function among lakes exposed to mining activities (n = 18) and non-exposed reference lakes (n = 8). Lake water quality data was used to cluster lakes into groups. Lake groups were then overlain onto multivariate ordinations derived from species composition-abundance data to determine if species composition was related to water quality. Ecosystem function variables included planktonic phosphorus cycling and planktonic respiration. The classified lake groups clustered well on ordinations derived from species composition-abundance data suggesting that relationships exist between water quality and plankton species composition. However, ecosystem function was similar among the majority of lakes and flooded pits despite differences in species richness, species composition and species abundance. Only a small number of aquatic systems had ecosystem function properties that were different from the majority of lakes and pits. These systems had the greatest concentrations of contaminants and had very low biodiversity (richness and evenness) compared to the other systems. Despite having differences in plankton species composition and species richness, all lake groups were functionally similar. This suggests that functional redundancy in species composition may be present in the majority of lakes and pits in such a way that ecosystem function is maintained.
12

The relationship between environmental agreements and environmental impact assessment follow-up in Saskatchewan's uranium industry

Birk, Jasmine Angie 27 May 2009 (has links)
Environmental Impact Assessment (EIA) is a planning process used to predict, assess, mitigate, and monitor the potential environmental and social impacts that may be associated with a proposed development project. Essential to the efficacy of EIA is follow-up - a post-decision process that attempts to understand EIA outcomes and provides feedback on project development and learning processes to improve environmental management practices. While considerable literature on follow-up related themes exists, the actual implementation and engagement of all stakeholders involved with follow-up in post-consent decision stages lacks or is not done well. That being said, in northern Canada, and in the mining sector in general, much of this post-decision activity is occurring under a new institutional arrangement: privatized community-industry Environmental Agreements and associated community-based monitoring programs. Based on a case study of follow-up in northern Saskatchewans uranium mining industry, this thesis examines both the institutional development of EIA follow-up and the role and contribution of community-based Environmental Agreements to EIA follow-up and impact management practices. This thesis adopted a manuscript-style format; both utilized a combined methodology of document review and semi-structured interviews. The first manuscript focuses on the institutional development of follow-up in the northern Saskatchewan uranium mining industry, giving context to the current situation. Results demonstrate that follow-up in Saskatchewans uranium industry has transformed and is characterized by four themes ranging from little or no follow-up to a new system that now includes a participatory yet privatized process based on privatized agreements. Results suggest that follow-up has evolved to a current emphasis on environmental management incorporating a community-centric approach, recognition of socioeconomic issues in monitoring programs, and an increased community and industry presence in follow-up and monitoring activities. The second manuscript examines the nature and scope of the northern Saskatchewan uranium industrys Environmental Agreement and its potential role in EIA follow-up. Results indicate that although privatized Environmental Agreements and community-led monitoring programs complement and supplement formal EIA follow-up processes and contribute to environmental management practices, they do not have the capacity to replace EIA follow-up. Results from this thesis advance current knowledge and understanding of the evolution of EIA follow-up and the current role and contribution of privatized agreements to post-decision follow-up and impact management practices.
13

Modeling energy consumption in the mining and milling of uranium

Tavrides, Emily Loree 16 February 2011 (has links)
A family of top-down statistical models describing energy consumption in the mining, milling, and refining of uranium are formulated. The purpose of the models is to estimate the energy-to-grade dependence for uranium extraction, while defining a minimum grade that can be feasibly mined and produced. The results serve as a basis for understanding the factors governing energy consumption in the production of U3O8. The models are applied to a considerably larger data set of operating mines than in any previous effort. In addition, the validity of the modeling approach is established by modeling energy for two other commodities, gold and copper, thereby showing it can be applied to other metals. Statistical measures of explanatory power show that the models the energy-to-grade relationship is well-described for both uranium and gold. For copper, there was insufficient data over a broad range of ore grades to obtain a model that passed statistical confidence measures. The results show that mining of lower-grade deposits of uranium is likely to be less energy-intensive than previous investigators concluded. It is shown that the uncertainty in the results is dominated by the contribution of the grade-independent component of energy consumption. / text
14

Rabbit Lake

2014 August 1900 (has links)
Rabbit Lake explores the concerns of citizens who testified at hearings held by the Rabbit Lake Uranium Mine Environmental Assessment Panel throughout Saskatchewan in 1993. The poems that form my thesis are both lyrical and experimental, derived in part from the voices found in the Rabbit Lake transcripts. Inspired by rhizome theory and rhizomorphous structures, the voices in my thesis are nomadic: their primary impulse is to map interconnected histories and geographies; in so doing, these voices transcend boundaries and coalesce to form a polyphonic, non-linear narrative. The influence of ecocritical theory is reflected in poems that draw the reader’s attention to the non-human world affected by uranium mining, most notably in an interspersed series of experiments detailing various forms of lichen found throughout Saskatchewan. Various other textual experiments, including collage and erasure, are lines of flight within the rhizome of the thesis. The inclusion of “(inaudible)” passages found in the transcripts is intended to draw the reader’s attention toward what was misheard or left unsaid at the hearings. The presence of an “unknown” speaker is designed as a poetic and political intervention that enables elaborations. Beginning with Canada’s historical involvement in the Manhattan Project, that is, the United States’ earliest attempt to build a nuclear weapon, my thesis moves from Great Bear Lake, Northwest Territories, and into the lakes and waterways of Saskatchewan’s north. The voices that emerge, situated in association with lakes and rivers, include a chorus of women and a chorus of Indigenous elders, an invented uranium mining corporation, “Uraneco,” and several scientists, including a biologist and geophysicist, as well as an invented cosmochemist and limnologist. From Saskatchewan’s northern waterways, the voices wander outward, evoking sites affected by the nuclear industry beyond Saskatchewan’s borders, from crops in the province’s south historically affected by fallout from nuclear weapons’ testing in Nevada, to radioactive detritus left in the deserts of Iraq due the United States’ use of depleted Canadian uranium in munitions. The intention behind this figurative explosion of the thesis is to illustrate the extent to which a seemingly isolated uranium mine may affect the whole world.
15

The environmental regulation of uranium mines in Namibia : a project life cycle analysis / Louw A.

Louw, Alet. January 2012 (has links)
Uranium exploration and mining activities in Namibia have increased rapidly since 2003, which increase not only poses a significant impact on the country’s economy, but also on its unique and pristine natural environment. The nature and extent of the environmental impacts associated with uranium mining requires a sound environmental law and policy framework that regulates uranium activities, impacts and aspects during each phase of the project life cycle of a uranium mine. It also requires of authorities to establish and enhance environmental protection and sustainability during uranium mining operations and to ensure that all environmental impacts that inevitably occur as a result of uranium mining activities are addressed in a holistic and integrated manner during each phase of the project life cycle of a uranium mine. In order to do this the country must develop and maintain an efficient and effective environmental governance regime. Namibia’s environmental law and policy framework that regulates uranium mining does not cover the entire PLC of uranium mining. It is vital that the current loops in the country’s existing environmental regulatory framework be closed and that an efficient and effective environmental governance regime, as envisaged in this study, be established. This will enable the administering agents to actively promote and maintain the welfare of the people, ecosystems, essential ecological processes and the biodiversity of Namibia, as well as the utilisation of living natural resources on a sustainable basis to the benefit of all Namibians, both present and future, as pledged in the Namibian Constitution. / Thesis (LL.M. (Environmental law))--North-West University, Potchefstroom Campus, 2012.
16

The environmental regulation of uranium mines in Namibia : a project life cycle analysis / Louw A.

Louw, Alet. January 2012 (has links)
Uranium exploration and mining activities in Namibia have increased rapidly since 2003, which increase not only poses a significant impact on the country’s economy, but also on its unique and pristine natural environment. The nature and extent of the environmental impacts associated with uranium mining requires a sound environmental law and policy framework that regulates uranium activities, impacts and aspects during each phase of the project life cycle of a uranium mine. It also requires of authorities to establish and enhance environmental protection and sustainability during uranium mining operations and to ensure that all environmental impacts that inevitably occur as a result of uranium mining activities are addressed in a holistic and integrated manner during each phase of the project life cycle of a uranium mine. In order to do this the country must develop and maintain an efficient and effective environmental governance regime. Namibia’s environmental law and policy framework that regulates uranium mining does not cover the entire PLC of uranium mining. It is vital that the current loops in the country’s existing environmental regulatory framework be closed and that an efficient and effective environmental governance regime, as envisaged in this study, be established. This will enable the administering agents to actively promote and maintain the welfare of the people, ecosystems, essential ecological processes and the biodiversity of Namibia, as well as the utilisation of living natural resources on a sustainable basis to the benefit of all Namibians, both present and future, as pledged in the Namibian Constitution. / Thesis (LL.M. (Environmental law))--North-West University, Potchefstroom Campus, 2012.
17

Avaliação in situ da biogeodisponibilidade de metais em área de mineração usando as técnicas de peixes transplantados e DGT / In situ evaluation of the biogeoavailability of metals in a mining area using transplanted fishes and DGT techniques

Eismann, Carlos Eduardo [UNESP] 14 November 2017 (has links)
Submitted by CARLOS EDUARDO EISMANN null (kadueismann@gmail.com) on 2018-01-05T14:55:15Z No. of bitstreams: 1 Dissertação Carlos Eduardo Eismann.pdf: 1179566 bytes, checksum: 31c2f0993986aed5992b2088ac3153cb (MD5) / Rejected by Adriana Aparecida Puerta null (dripuerta@rc.unesp.br), reason: Prezado Carlos Eduardo Eismann, Solicitamos que realize uma nova submissão seguindo as orientações abaixo: - Capa - Faltou a capa no documento enviado. - Folha de Aprovação (faltou) Estes itens são elementos obrigatórios de acordo com as normas de trabalhos do seu Programa de Pós Graduação. Agradecemos a compreensão e aguardamos o envio do novo arquivo. Atenciosamente, Biblioteca Campus Rio Claro Repositório Institucional UNESP on 2018-01-08T18:12:45Z (GMT) / Submitted by CARLOS EDUARDO EISMANN null (kadueismann@gmail.com) on 2018-01-09T12:39:53Z No. of bitstreams: 1 Dissertação Carlos Eduardo Eismann.pdf: 1285572 bytes, checksum: b10940da816026c45e4e6fa92a5d4807 (MD5) / Approved for entry into archive by Adriana Aparecida Puerta null (dripuerta@rc.unesp.br) on 2018-01-09T18:37:35Z (GMT) No. of bitstreams: 1 eismann_ce_me_rcla.pdf: 1252029 bytes, checksum: 63e1b3228ec61f7168a0ff587899bcec (MD5) / Made available in DSpace on 2018-01-09T18:37:35Z (GMT). No. of bitstreams: 1 eismann_ce_me_rcla.pdf: 1252029 bytes, checksum: 63e1b3228ec61f7168a0ff587899bcec (MD5) Previous issue date: 2017-11-14 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A toxicidade e biodisponibilidade dos metais presentes no ambiente estão diretamente relacionadas com as suas condições de especiação. A avaliação in situ da biogeodisponibilidade de metais é uma ferramenta importante na manutenção da qualidade ambiental dos sistemas aquáticos. A técnica DGT (do inglês Diffusive Gradient in Thin Films) e o uso de animais transplantados são capazes de fornecer informações desta natureza. As biodisponibilidades de Al, Fe, Mn e Zn em águas de três pontos no interior de uma área de mineração desativada no município de Caldas-MG, Brasil, foram avaliadas utilizando-se a técnica DGT e exemplares transplantados do peixe Oreochromis niloticus. As amostragens foram realizadas em períodos de 14, 28 e 42 dias. Foram utilizados dispositivos DGT com géis difusivos e restritivos e foram determinadas as concentrações de Al, Fe, Mn e Zn nos fígados, brânquias e músculos dos peixes após digestão ácida em microondas. As determinações das concentrações dos analitos nas amostras foram realizadas por Espectrometria de Emissão Óptica com Plasma acoplado Indutivamente (ICP-OES). A massa acumulada nos dispositivos com géis restritivos foi maior que com os géis difusivos, indicando uma possível contribuição da fração moderadamente lábil na massa acumulada nos dispositivos. Os resultados da DGT indicaram uma presença de concentrações muitos baixas de espécies orgânicas destes elementos em todos os pontos estudados. As maiores frações de Al, Fe, Mn e Zn foram identificadas nos pontos 014, 023, 023 e 041 respectivamente. O método proposto se mostrou satisfatório para determinar as concentrações de Al, Fe, Mn e Zn em todas as amostras dos tecidos de O. niloticus. Foram observados incrementos significativos nas concentrações de Mn e Zn nas brânquias dos exemplares transplantados quando comparados com aqueles não transplantados. As concentrações lábeis foram mais satisfatórias do que as concentrações dissolvidas em predizer a variabilidade espacial das concentrações biodisponíveis de Al, Fe, Mn e Zn. / The toxicity and bioavailability of metals in the environment is directly associated to its speciation conditions. The in situ evaluation of the biogeoavailability of metals is an important tool to support the environmental quality of aquatic systems. The DGT technique (Diffusive Gradients in Thin Films) and the use of transplanted animals are able to give this kind of information. The bioavailability of Al, Fe, Mn and Zn was evaluated at three points inside a disabled uranium mining site at Caldas city, Brazil, using DGT technique and transplanted specimens of the fish Oreochromis niloticus. The samplings were performed in periods of 14, 28 and 42 days. The DGT devices were deployed using diffusive and restrictive gels and the Al, Fe, Mn and Zn concentrations were determined at the kidney, gill and muscle of the fishes after an acid digestion using a microwave. The determinations of the analytes were performed by Inductively Coupled Plasma Optic Emission Spectrometry (ICP-OES). The accumulated mass in the devices using restrictive gels was higher than using diffusive gel, indicating that there’s probably a contribution of the moderately labile fractions to the accumulated mass of these devices. Results from DGT indicated the presence of very low concentrations of organic species of Al, Fe, Mn and Zn in all the sampling points. The highest labile fraction of Al, Fe, Mn and Zn were observed at points 014, 023, 023 e 041 respectively. The proposed method was satisfactory in determining the concentration of Al, Fe, Mn e Zn in all the tissue samples of O. niloticus. A significant increase of the Mn and Zn concentrations was observed in the gills of the transplanted specimens when comparing to the not transplanted ones. The labile concentrations were more satisfactory predicting the spatial variability of the bioavailable Al, Fe, Mn and Zn concentrations than the dissolved concentrations.
18

Dinâmica das águas subterrâneas e mecanismos de recarga em uma área de mineração de urânio empregando técnicas isotópicas

Araújo, Valeska Peres de, Instituto de Engenharia Nuclear January 2017 (has links)
Submitted by Marcele Costal de Castro (costalcastro@gmail.com) on 2017-11-06T16:09:39Z No. of bitstreams: 1 VALESKA PERES DE ARAUJO D.pdf: 19050366 bytes, checksum: a130a4b8dc02de3bc8bae53d77530112 (MD5) / Made available in DSpace on 2017-11-06T16:09:39Z (GMT). No. of bitstreams: 1 VALESKA PERES DE ARAUJO D.pdf: 19050366 bytes, checksum: a130a4b8dc02de3bc8bae53d77530112 (MD5) Previous issue date: 2017 / Em regiões áridas e semiáridas, a água superficial não está disponível de forma perene, e as águas subterrâneas proporcionam, na maioria dos casos, a única fonte de água permanente e segura. Esta situação é particularmente verdadeira na Bacia Experimental Caetité (BEC), localizada na região semiárida do Nordeste do Brasil, onde a comunidade local é fortemente dependente da disponibilidade de águas subterrâneas. A questão da água se agravou em 1999, com o início das operações de uma instalação nuclear, a Unidade de Concentrado de Urânio (URA), e a comunidade local teve que enfrentar não apenas os desafios associados à escassez de água, mas também os potenciais processos de contaminação decorrentes da atividade de mineração. Este cenário provocou um debate crescente entre a comunidade local e o centro de produção de urânio. Embora vários estudos venham sendo conduzidos na região, o regime de fluxo de águas subterrâneas nesta bacia hidrográfica permanece mal compreendido. Este estudo tem como objetivo investigar a dinâmica das águas subterrâneas e mecanismos de recarga nesta bacia, como parte dos esforços iniciais para caracterizar a hidrogeologia desta área afim de subsidiar futuros estudos de contaminação. Medidas de δ2H, δ 18O, total de sólidos dissolvidos (TSD), pH e condutividade elétrica (EC) foram realizadas em um total de 181 amostras (122 águas subterrâneas, 36 águas superficiais e 23 amostras de precipitação) coletadas durante as estações secas e chuvosas de 2012 a 2014. Os resultados químicos, físico-químicos e isotópicos sugerem que a recarga é espacialmente variável, correndo por mecanismo direto e indireto, por precipitação local e contribuição da água superficial, respectivamente. Estes resultados apontam para uma dinâmica rápida deste sistema, tornando-o mais vulnerável à contaminação por atividades na superfície do terreno, uma vez que os contaminantes podem rapidamente atingir o aquífero. / In arid and semi-arid regions, where surface water is not available on fixed basis, groundwater provides in most cases the only permanent and safe source of water. This situation is particularly true in the Caetité Experimental Basin (CEB), located in the semi-arid region of Northeastern Brazil, where the local community depends heavily on groundwater availability. The water issue has been aggravated since 1999 when a nuclear facility, the Uranium Concentrate Unit (URA), started operations and the local community had to face not only the challenges associated with water scarcity but also the potential contamination processes due to mining activity. This scenario caused an increasing debate over competing water interests between the local community and the uranium production center. Although several studies have been conducted to characterize the hydrological system of the region, the groundwater flow regime in this watershed remains poorly understood. This study aims to investigate the groundwater dynamics and recharge mechanisms in this basin, as part of initial efforts to characterize the hydrogeology of this area for future contamination studies. Measurements of δ2H, δ18O, total dissolved solids (TDS), pH, and electrical conductivity (EC) were carried out in a total of 181 samples (122 groundwater, 36 surface water and 23 rainfall samples), collected during the dry and wet seasons from 2012 to 2014. The chemical, physicochemical and Isotope results suggest that the recharge is spatially variable, occurring by direct and indirect mechanism, by local precipitation and surface water contribution, respectively. These results point to a fast dynamic of this system, which makes this aquifer more vulnerable to contamination from activities in the land surface, as the contaminants could move and quickly reach the aquifer.
19

Jáchymover Uranerz und Radioaktivitätsforschung um die Wende des 19./20. Jahrhunderts

Seidlerová, Irena, Seidler, Jan January 2010 (has links)
Auf der Grundlage umfangreicher Originaldokumente aus staatlichen Archiven in Prag und Wien zeichnen die Autoren anhand zahlreicher Briefe, Aktennotizen und weiterer Aufzeichnungen die Rolle der Joachimstaler Uranbergwerke bei der Bereitstellung von Pechblende nach, die als Mineral M. und P. Curie die Entdeckung des Elementes Radium ermöglichten. Bürokratische Eitelkeiten, akademische Vorurteile und sich überschneidende Interessen der K.u.K. Verwaltung in Wien haben die durchaus denkbare Entdeckung des Radiums in österreichischen Laboratorien erfolgreich verhindert.
20

Vliv těžební činnosti na krajinný ráz v okolí města Příbram / The influence of mining activities on the landscape surrounding the town Příbram

Fišerová, Šárka January 2016 (has links)
This diploma thesis attends to the landscape character, the methodics of the evaluation of landscape character and the influence of mining on the landscape character. Příbram, influenced by uranium mining during last century, was chosen as a model area. The aim of this thesis is a comparison of chosen methodics of the evaluation of landscape character in the term of mining district and a creation of new methodics specialized for model area. The thesis focus on the landscape character and restoration ecology in mining areas in theoretical part. There is a description of landscape character protection and preservation, also in terms of law, reclamations and uranium mining. Below, the four chosen methodics are mentioned. In practical part, the diploma thesis characterizes the model area, its history and also current situation including reclamation made. Then there are a comparison of chosen methodics of landscape character evaluation according to elected criteria and a project of methodics for to a evaluation of chosen area. Powered by TCPDF (www.tcpdf.org)

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